Heyy, I had sex with my boyfriend for the first time on 27th September, 7/8 days before my period. He didn't ejaculate inside me and it lasted 10-20 seconds and then we used a condom as he feared he might cum. Now my period is 3 days late. I did take the test on Friday, it was negative. I have been getting cramps on my left side of the abdomen, which feel like my normal period cramps and have a feeling of wetness, but there is no period. So, having sex for the first time can change your cycle right? And usually by how long? Also, what are the chances I am pregnant? I have a 25/26 days cycle, my last period was on 9th September.